The proposed research examines in the course of a longitudinal study, changes in the frontal lobe functions of both healthy older adults and individuals with Alzheimer's disease (AD). Specifically, we are concerned with the frontal and prefrontal lobes' involvement in memory tasks dealing with (1) planning or rule-guided behavior and (2) the encoding of conceptual and perceptual features of both verbal and motor stimuli. Both the clinical description and diagnostic criteria for AD emphasize the progressive nature of the memory impairment and general cognitive degeneration. However, relatively little empirical data is available on the course of memory deterioration in this disease. This is especially true in terms of our knowledge of how these individuals process psychomotor and movement-based information. The lack of research on motor memory in AD is surprising as AD patients typically show little deterioration in motor function until relatively late in the disease. The proposed research will examine changes in the motor and verbal short-term memory of healthy older adults and patients with mild-to-moderately severe AD. More specifically, the tasks examine release from proactive interference in both verbal and motor memory, as well as the recall of subject-and experimenter-defined movements. By examining differences in how AD patients process verbal and motor information, we can determining whether or not their encoding impairments represents a generalized deficiency or is limited to specific types of information. That is, does memory decline uniformly, or is there a different pattern of decline for different types of information. Secondly, as the tasks examine planning and susceptibility. Finally, the use of motor memory tasks may provide a promising methodology or new approach to assessing the course of cognitive decline in AD.